Prime Factorization

Find the prime Factorization of the following:

1. 21

2. 130

3. 84

3 x 7

2 x 5 x 13

2 x 2 x 3 x 7

The Combination for the lock on Jacoby’s suitcase is based on the prime factorization of 315. What is the combination?

a. 5 x 7 x 9

b. 3 x 7 x 15

c. 3 x 3 x 5 x 7

d. 2 x 3 x 3 x 5 x 7

c. 3 x 3 x 5 x 7

Chris left out one prime factor when he wrote this prime factorization for 168.

2 x 2 x 2 x 3 x What is the missing prime factor?

a. 2b. 3c. 5d. 7

7

Logan left out one prime factor when she wrote this prime factorization for 1092.

2 x 2 x x 7 x 13What is the missing prime factor?

a. 2b. 3c. 7d. 13

3

The combination lock is a 3-digit number. The digits are the prime factors of 42 listed from greatest to least. What is the combination for the lock?

7 - 3 - 2

What are the first 10 multiples for 4?

4,8,12,16,20,24,28,32,36,40

What are the first 10 multiples for 10?

10,20,30,40,50,60,70,80,90,100

What numbers appear in both lists? 20 and 40

What is the Least Common Mutliple?

20

Find the Least Common Multiple for each set of numbers:

1. 5 and 20

2. 6 and 15

3. 12 and 30

20

30

60

Mark purchases materials to make watches for a jewelry show. There were 6 watch faces in a pack and 9 watch bands in a pack. What is the least number of watches Mark can make without having any supplies left over?

Kaley purchases materials to make dog collars for a pet show. There are 6 buckles in a pack and 8 straps in a pack. What is the least number of dog collars Kaley can make without having any supplies left over?

Penc ils are sold in packages of 10, and erasers are sold in packages of 6. What is the least number of pencils and erasers you can buy so that there is one pencil for each eraser with none left over?